What makes EF-hands clap?

SCAN Seminar

Title: What makes EF-hands clap? Two examples of structural and functional diversity among neuronal EF-hand proteins.

Speaker: Malgorzata Palczewska

Affiliation: Molecular Interactions and NMR

Abstract:

The EF-hand family group is a large family, with over 30 known subfamilies, present in all kingdoms of the living world and all cell types. EF-hand proteins play a key role in calcium-dependent signaling pathways. The EF-hand is a ~30 residue, helix-loop-helix motif. Calmodulin is the best known EF-hand protein, containing four EF-hand motifs paired into two EF-domains. Calcium-binding to calmodulin results in a reorientation of the helices and the exposure of a large hydrophpobic surface area. This surface is used to bind to, and activate, a large number of targets. Other EF-hand proteins interact with only a few specific targets. The conformational basis for target binding and activation are varied despite the conserved EF-domain structure.  In recent years it has become apparent that calcium is not the only factor in EF-hand protein function, and that cofactors can subtly influence the cellular functions of these proteins.

In our lab, we are involved in conformational and functional studies of representatives of two EF-hand subfamilies: DREAM (also known as KChIP3 and calsenilin) from the NCS family and all three proteins constituting the six EFhand (HEF) subfamily of EF-hand proteins. During my talk I will present data and our future plans towards understanding the versatility of DREAM proteins by means of its oligomerization and our approach to study HEF functions through cofactors other than calcium.